Handwriting capture device

ABSTRACT

A handwriting capture device which employs a highly sensitive digitizer to accurately capture signature information entered using a writing force greater than or equal to a predetermined writing force. The handwriting capture device includes a housing having a top surface, a resistive membrane digitizer mounted in the top surface and having a low pattern density, a layer of urethane rubber for frictionally holding the receipt in place, circuitry for processing digitizer information, a clamp for retaining a receipt in place over the digitizer during movement of the device, and circuitry for sensing the presence of the receipt and for activating data capture by the digitizer when the receipt is positioned under the clamp. In the preferred embodiment, the clamp also serves to minimize finger contact with the digitizer.

CROSS REFERENCE TO RELATED APPLICATION

The present invention is related to commonly assigned and co-pendingU.S. application entitled, "Write Input Transaction Apparatus andMethod", filed Aug. 30, 1990, invented by Allgeier et al., and having aSer. No. 07/575,096.

BACKGROUND OF THE INVENTION

The present invention relates to signature capture devices and morespecifically to a handwriting capture device.

Today, retailers are burdened with having to store and retrieve largeamounts of paper records from credit and check transactions. Normally,these records are produced at a retail terminal as master copies ofsales receipts, and which are removed from the terminal at the end ofthe business day for balancing and entry into accounting journals andshipment to processing and storage facilities. Allgeier et al. disclosesa write input device employing a display underneath a transparentdigitizer to capture signature information. The display gives a customerfeedback for stylus input.

While the Allgeier et al. device works well, having a liquid crystaldisplay makes it expensive. Therefore, it would be desirable toeliminate the display and reduce the cost by using a low-cost resistivemembrane digitizer. The low-cost resistive membrane must function inresponse to minimal signing force applied by an ordinary writinginstrument such as a pen.

The use of pressure-sensitive resistive membrane digitizers is subjectto false actuations, including those caused by finger contact. If thedigitizer is shorted by finger contact during signing, the digitizedpoints representing the signature will be obscured by the finger points,resulting in random scribbling in place of the signature.

The sensitivity of a pressure-sensitive digitizer is determined by thedensity of the spacer dot pattern, which maintains separation betweenthe top and bottom sheets of the digitizer. The more dense the patternis, the more resistant the digitizer is to finger actuation. However, ahigh pattern density requires more writing force to capture a signature.In systems without displays or other sources of immediate feedback, itis essential that the digitizer be sensitive to writing force.

Therefore, it would be desirable to provide a handwriting capture devicewithout a display, but having a digitizer sensitive to minimal writingforce.

SUMMARY OF THE INVENTION

In accordance with the teachings of the present invention, a handwritingcapture device is provided. The handwriting capture device includes ahousing having a top surface, a pressure-sensitive digitizer having alow pattern density and mounted in the top surface, circuitry forsensing the presence of a receipt and activating the digitizer,circuitry for processing signature information from the digitizer, and aclamp for retaining the receipt in place over the digitizer. In thepreferred embodiment, the clamp also serves to minimize finger contactwith the digitizer.

It is accordingly an object of the present invention to provide ahandwriting capture device.

It is another object of the present invention to provide a handwritingcapture device, which is less expensive than a handwriting capturedevice employing a liquid crystal display mounted beneath a transparentdigitizer.

It is another object of the present invention to provide a handwritingcapture device which employs a highly sensitive low-cost digitizer whichcan capture signatures entered using minimal force from an ordinarywriting instrument, such as a ballpoint pen.

It is another object of the present invention to provide a handwritingcapture device which employs a clamp for holding a pre-printed receiptin place over the digitizer for signature.

It is another object of the present invention to provide a handwritingcapture device which employs a clamp for holding a pre-printed receiptin place over the digitizer for signature and which minimizes fingercontact with the digitizer.

It is another object of the present invention to provide a handwritingcapture device which is lightweight, hand-held, and portable.

BRIEF DESCRIPTION OF THE DRAWINGS

Additional benefits and advantages of the present invention will becomeapparent to those skilled in the art to which this invention relatesfrom the subsequent, description of the preferred embodiments and theappended claims, taken in conjunction with the accompanying drawings, inwhich:

FIG. 1 is a perspective view of a first embodiment of the handwritingcapture device of the present invention;

FIG. 2 is a sectional view of the handwriting capture device taken alongline 2--2 of FIG. 1.

FIG. 3 is a sectional view of the handwriting capture device of thepresent invention taken along lines 3--3 of FIG. 1;

FIG. 4 is a perspective view of a second embodiment of the handwritingcapture device of the present invention; and

FIG. 5 is a sectional view of the handwriting capture device of thepresent invention taken along line 5--5 of FIG. 4.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Turning now to FIGS. 1 and 2, a first embodiment of the handwritingcapture device 10 of the present invention is shown. The handwritingcapture device 10 includes a housing 12 having a bottom supportingsurface 14 and a top surface 16. In this embodiment, the housing 12 isgenerally rectangular in shape. The handwriting capture device 10 islightweight and portable. The left end of the housing 12 is sufficientin width and depth to facilitate grasping of the housing 12.

Within the top surface 16 is a pressure-sensitive digitizer 18, althoughother types of digitizers are also envisioned. The digitizer 18 issensitive to signing forces greater than or equal to a predeterminedminimum signing force, which is no more than about 10 to 15 grams. Whena pen is used, the digitizer has a sensitivity sufficient to capture ahandwriting that produces a legible ink impression on the receipt. Inthis embodiment, a digitizer manufactured by W. H. Brady & Co. andhaving a part number 2500044089 is used. This digitizer has a nearseparation between dots of 0.2 inches. Dot separations higher than 0.2are not recommended because spurious digitizer readings are more likelyto occur. Digitizers having dot separations as low as 0.16 inches may beused in the present invention to achieve valid handwriting capture.

A thin layer of urethane rubber 19 is affixed to the top surface of thedigitizer 18. The urethane rubber 19 provides a high friction surfacefor keeping the receipt 22 in place. A signature line 20 on the uppersurface 16 and to the left of the digitizer acts as a guide for liningup a receipt 22 having a signature line 21.

Also within the housing 12 is the electronic processing circuitry 24 foroperating the digitizer 18 and for controlling information flow from thedigitizer 18 to a point-of-service (POS) terminal (not shown). Thedigitizer 18 is coupled to the electronic circuitry 24 by a wireconnector 27 and the electronic circuitry 24 is coupled to the POSterminal by a wire cable 26. The housing may also include circuitry 25for sensing the presence of the receipt 22 and activating the digitizer18. In this embodiment, circuitry 25 includes a commercially availableoptical switch having an emitting side and a receiving side, both onopposite sides of the receipt. The sensing circuit 25 activates datacapture by the digitizer 18 when the receipt 22 is in position under aclamp 30 so as to minimize acceptance of false actuations.

The paper receipt 22 from the POS terminal is properly aligned and heldin place during movement of the device 10 by the clamp 30 which isintegrally located on the top surface 16 at the right end of the housing12. The clamp 30 includes an inverted, generally L-shaped member 32having an inner surface 34. A vertical portion 36 of the inner surface34 provides a stop against which the receipt 22 is aligned. A horizontalportion 38 of the inner surface 34 holds the receipt 22 in contact withthe top surface 16 of the housing 12. The distance from the horizontalsurface 38 to the top surface 16 is sufficient to allow a receipt 22 topass between the two surfaces. The clamp 30 also includes an upwardlyflared portion 40 at one end to facilitate insertion of the receipt 22into the clamp 30.

Referring now to FIG. 3, the horizontal portion 38 of the inner surface34 includes downwardly facing protrusions 42 which are generallyhemispherical in shape in order to fixedly retain the receipt 22 inplace. Correspondingly shaped receptacles or dimples 44 are located inthe top surface 16 below the protrusions 42. In combination, the dimples44 and protrusions 42 act to increase the frictional force between thetop surface 16 and the receipt 22, thereby effectively retardingmovement of the receipt 22 out of the clamp 30.

In operation, a POS operator inserts the right edge of the receipt intothe clamp 30, starting at the upwardly flared portion 40. The receipt 22is further inserted until the signature line 21 is properly aligned withthe signature line 20 on the top surface 16 of the housing 12. In thisposition, the receipt 22 will also be properly aligned with the verticalsurface 36 of the clamp 30 and properly engaged between the dimples 44and the protrusions 42. The sensing circuitry 25 activates data captureby the digitizer 18. A customer then signs his name with a writingdevice, such as a pen, on the signature line 21. Advantageously, thehandwriting capture device 10 is lightweight and can be easilytransferred from person to person without dropping the receipt 22.

Referring now to FIGS. 4 and 5, a second and preferred embodiment 50 ofthe handwriting capture device of the present invention is shown. Likethe first embodiment, the preferred embodiment 50 includes a housing 52having a top surface 54, electronic processing circuitry 56 within thehousing 52, sensing circuitry 57 within the clamp 30, and a digitizer 18within the top surface 54. The same considerations as in the firstembodiment regarding digitizer choices apply in this embodiment. A thinlayer of urethane rubber 19 is affixed to the top surface of thedigitizer 18 to provide a high friction surface for keeping the receipt22 in place. The electronic processing circuitry 56 is coupled to thedigitizer 18 through a wire connector 60 and to a POS terminal (notshown) through a wire cable 62.

In addition, the housing 52 includes a top member 63 and a base member64 which is inclined to facilitate writing. In order to properly align areceipt 22 for signature, the housing 52 includes a guide member 66 onthe top surface 54 at one end of the housing 52. The guide member 66 hasa vertical guide surface 68 against which the receipt 22 is aligned. Thehousing 52 is sufficient in width and depth to facilitate grasping ofthe housing 52.

The preferred embodiment also includes a clamp 70 for retaining thereceipt 22 in place during movement of the device 50. The clamp 70includes a frame member 72 which is generally rectangular in shape andwhich is made of transparent plastic to allow a customer to view theitemized information on the receipt 22 while signing. The clamp 70 isanchored at its left end and its right end is biased against the topsurface 54 of the housing 52. Centrally located within the clamp 70 is arectangular window 76 exposing the digitizer 18 below. The window 76facilitates proper installation of the receipt 22 over the digitizer 18and serves to quickly orient a customer with the correct location 78 forsigning. The clamp 70 may also include an upwardly flared portion 74 forfacilitating insertion of the receipt 22 under the clamp.

Advantageously, the clamp 70 also serves to minimize finger contact withthe digitizer 18. The clamp 70 includes a vertical rib 80 extendingacross the clamp 70 for guarding the digitizer 18 from the thumb of theleft hand of a customer writing with his right hand and also restrictsaccess to the digitizer 18 by a customer writing with his left hand. Theframe member 72 blocks contact with the digitizer 18 by the right hand.In addition, the window 76 provides insufficient room for fingerplacement, forcing finger placement on the pen to be a predetermineddistance upwards from the pen tip for both right and left-handedcustomers.

In operation, a POS operator holds the device 50 in one hand and insertsthe receipt using the other hand by slipping the receipt 22 under theupwardly flared portion 74 until the receipt 22 rests against thevertical guide surface 68 and the signature line 78 or box 79 is withinthe window 76. A customer then signs his name with a writing device,such as a pen, on the signature line 78. Advantageously, the clampdesign facilitates one-handed insertion of the receipt 22. Also, thehandwriting capture device 50 is lightweight and can be easilytransferred from person to person without dropping the receipt 22.

Although the invention has been described with particular reference tocertain preferred embodiments thereof, variations and modifications ofthe present invention can be effected within the spirit and scope of thefollowing claims.

What is claimed is:
 1. A handwriting capture device comprising:a housinghaving a top surface; a digitizer, mounted within the top surface;retaining means located externally on the top surface for holding anexternally provided record member in a predetermined position on the topsurface; and means coupled to the digitizer for processing writteninformation.
 2. The handwriting capture device as recited in claim 1,wherein the digitizer is a pressure-sensitive digitizer.
 3. Thehandwriting capture device as recited in claim 2, wherein the digitizeris sensitive to a signing force greater than or equal to a predeterminedminimum signing force from a writing instrument applied to the recordmember over the digitizer.
 4. The handwriting capture device as recitedin claim 1, further comprising means coupled to the digitizer forsensing the presence of the record member and for activating datacapture by the digitizer when the record member is positioned under theretaining means.
 5. The handwriting capture device as recited in claim1, wherein the retaining means comprises a clamp over the record memberfor holding the record member in place during movement of the device. 6.The handwriting capture device as recited in claim 1, further comprisinga guard over the record member for minimizing finger contact with thedigitizer.
 7. The handwriting capture device as recited in claim 1,further comprising a guide on the top surface for aligning an edge ofthe record member along the guide.
 8. The handwriting capture device asrecited in claim 1, wherein the retaining means further comprises alayer of urethane rubber over the digitizer.
 9. The handwriting capturedevice as recited in claim 1, wherein the housing comprises:a top membercontaining the top surface, the top surface being inclined towards anoperator to facilitate handwriting; and a base member underneath the topmember.
 10. The handwriting capture device as recited in claim 5,wherein the clamp comprises:an inverted L-shaped member mounted on thetop surface of the housing having an inner horizontal surface and aninner vertical surface; a protrusion extending downwardly from the innerhorizontal surface; and a receptacle corresponding to the shape of theprotrusion within the top surface of the housing.
 11. The handwritingcapture device as recited in claim 10, wherein the protrusion andreceptacle are hemispherical in shape.
 12. The handwriting capturedevice as recited in claim 5, wherein the clamp has a window over thedigitizer.
 13. The handwriting capture device as recited in claim 5,wherein the clamp comprises:a frame member; and a window within theframe member and over the digitizer.
 14. The handwriting capture deviceas recited in claim 13, wherein the clamp further comprises an upwardlyflared portion at one end of the clamp for facilitating insertion of arecord member into the clamp.
 15. The handwriting capture device asrecited in claim 13, wherein the clamp is transparent.
 16. Thehandwriting capture device as recited in claim 6, wherein the guardcomprises:a frame member around the digitizer; and a vertical rib membermounted across the frame member.
 17. The handwriting capture device asrecited in claim 5, wherein the clamp is operative to hold the recordmember in place on the top surface of the housing during transfer of thedevice between a point-of-service operator and a customer.
 18. Thehandwriting capture device as recited in claim 5, wherein the clamp isalso operative to minimize finger contact with the digitizer.
 19. Thehandwriting capture device of claim 2, wherein the digitizer has upperand lower sheets electrically coupled at a plurality of dots by pressurefrom handwriting, the digitizer having a near separation between dots ofabout 0.16 to 0.2 inches.
 20. The handwriting capture device as recitedin claim 3, wherein the minimum signing force is no more than about 10to 15 grams.
 21. The handwriting capture device as recited in claim 2,wherein the digitizer has a sensitivity sufficient to capturehandwriting that produces a legible ink impression on the record member.22. A handwriting capture device comprising:housing having a topsurface; a pressure sensitive digitizer, mounted within the top surface,have upper and lower sheets electrically coupled at a plurality of dotsby pressure from handwriting, the digitizer having a near separationdistance between dots of about 0.16 to 0.2 inches, and being sensitiveto a predetermined minimum writing force of no more than about 10 to 15grams from an ordinary writing instrument applied to a paper receiptover the digitizer; means affixed to the digitizer of frictionallyholding the receipt in place, including a layer of urethane rubber; aguide for aligning an edge of the paper receipt; means coupled to thedigitizer and mounted within the housing for processing signatureinformation; means located externally on the top surface for holding anexternally provided receipt in place over the digitizer on the topsurface and for guarding the digitizer from finger contact including atransparent frame member, a window within the frame member over thedigitizer, and a rib member mounted across the frame member, saidholding and guarding means being operative to hold the receipt in placeon the top surface of the housing during transfer of the device betweena point-of-service operator and a customer; and means coupled to thedigitizer for sensing the presence of the receipt and for activatingdata capture by the digitizer when the receipt is positioned under theholding and guarding means.
 23. A method for capturing handwritingwithout immediate feedback from an electronic display comprising thesteps of:providing retaining means for holding an externally providedrecord member in a predetermined position on a digitizer; inserting therecord member between the retaining means and the digitizer; applying awriting to the digitizer through the record member; and processing asignal representing the writing from the digitizer.
 24. The method asrecited in claim 23, wherein the digitizer is a pressure-sensitivedigitizer.
 25. The method as recited in claim 24, wherein the digitizeris sensitive to a writing force greater than or equal to a predeterminedminimum writing force.
 26. The method as recited in claim 25, whereinthe minimum writing force is no more than about 10 to 15 grams.
 27. Themethod as recited in claim 24, wherein the digitizer has upper and lowersheets electrically coupled at a plurality of dots by pressure fromhandwriting and has a near separation distance between dots of about0.16 to 0.2 inches.
 28. The method as recited in claim 24, wherein thedigitizer has a sensitivity sufficient to capture handwriting thatproduces a legible ink impression on the record member.
 29. The methodas recited in claim 23, wherein the step of applying a writing comprisesthe substep of producing a legible ink impression on the record memberusing a pen.
 30. The method as recited in claim 23, wherein the step ofinserting the record member comprises a substep of aligning one edge ofthe record member along a guide mounted on the digitizer.
 31. The methodas recited in clam 23, further comprising the step of:guarding thedigitizer from finger contact.
 32. The method as recited in claim 31,further comprising the steps of:sensing the presence of the recordmember on the digitizer; and activating data capture by the digitizer inresponse to the sensing of the record member.
 33. The method as recitedin claim 23, wherein the record member has a reference mark.
 34. Themethod as recited in claim 33, wherein the reference mark is a signatureline.
 35. The method as recited in claim 33, wherein the reference markis a signature box.
 36. A handwriting capture device comprising:ahousing having a top surface; a digitizer, mounted within the topsurface; a clamp for holding a record member in a predetermined positionon the top surface, including an inverted L-shaped member mounted on thetop surface of the housing having an inner horizontal surface and aninner vertical surface, a protrusion extending downwardly from the innerhorizontal surface, and a receptacle corresponding to the shape of theprotrusion within the top surface of the housing; and means coupled tothe digitizer for processing written information.
 37. A handwritingcapture device comprising:a housing having a top surface; a digitizer,mounted within the top surface; a clamp for holding a record member in apredetermined position on the top surface, including an invertedL-shaped member mounted on the top surface of the housing having aninner horizontal surface and an inner vertical surface, a hemisphericalprotrusion extending downwardly from the inner horizontal surface, and ahemispherical receptacle corresponding to the shape of the protrusionwithin the top surface of the housing; and means coupled to thedigitizer for processing written information.
 38. A handwriting capturedevice comprising:a housing having a top surface; a digitizer, mountedwithin the top surface; a clamp for holding a record member in apredetermined position on the top surface, including a frame member, awindow within the frame member and over the digitizer, and an upwardlyflared portion at one end of the clamp for facilitating insertion of therecord member into the clamp; and means coupled to the digitizer forprocessing written information.